Quarter	Billions of US Dollars
1971-01-01	0.015
1971-04-01	0.015
1971-07-01	0.015
1971-10-01	0.015
1972-01-01	0.088
1972-04-01	0.088
1972-07-01	0.115
1972-10-01	0.136
1973-01-01	0.196
1973-04-01	0.262
1973-07-01	0.269
1973-10-01	0.252
1974-01-01	0.262
1974-04-01	0.263
1974-07-01	0.271
1974-10-01	0.338
1975-01-01	0.504
1975-04-01	0.701
1975-07-01	0.837
1975-10-01	1.372
1976-01-01	1.887
1976-04-01	2.155
1976-07-01	2.449
1976-10-01	2.826
1977-01-01	3.603
1977-04-01	4.490
1977-07-01	4.773
1977-10-01	5.890
1978-01-01	6.952
1978-04-01	7.664
1978-07-01	8.475
1978-10-01	9.315
1979-01-01	9.767
1979-04-01	10.232
1979-07-01	11.170
1979-10-01	11.336
1980-01-01	10.773
1980-04-01	11.664
1980-07-01	11.399
1980-10-01	10.672
1981-01-01	9.912
1981-04-01	9.145
1981-07-01	9.265
1981-10-01	9.721
1982-01-01	8.734
1982-04-01	8.326
1982-07-01	8.341
1982-10-01	8.610
1983-01-01	8.259
1983-04-01	7.713
1983-07-01	7.700
1983-10-01	7.321
1984-01-01	7.498
1984-04-01	7.043
1984-07-01	6.902
1984-10-01	7.063
1985-01-01	7.103
1985-04-01	7.351
1985-07-01	8.795
1985-10-01	8.481
1986-01-01	9.274
1986-04-01	10.451
1986-07-01	12.687
1986-10-01	13.939
1987-01-01	16.218
1987-04-01	17.123
1987-07-01	16.969
1987-10-01	18.269
1988-01-01	19.050
1988-04-01	19.867
1988-07-01	20.133
1988-10-01	20.987
1989-01-01	21.459
1989-04-01	20.902
1989-07-01	21.159
1989-10-01	22.064
1990-01-01	21.072
1990-04-01	21.229
1990-07-01	21.757
1990-10-01	21.760
1991-01-01	19.901
1991-04-01	19.259
1991-07-01	20.769
1991-10-01	21.706
1992-01-01	20.844
1992-04-01	23.013
1992-07-01	23.316
1992-10-01	21.321
1993-01-01	21.284
1993-04-01	21.604
1993-07-01	21.077
1993-10-01	20.167
1994-01-01	19.892
1994-04-01	19.985
1994-07-01	20.331
1994-10-01	19.704
1995-01-01	20.169
1995-04-01	19.458
1995-07-01	19.087
1995-10-01	19.118
1996-01-01	19.241
1996-04-01	19.478
1996-07-01	18.733
1996-10-01	19.147
1997-01-01	17.779
1997-04-01	17.301
1997-07-01	21.034
1997-10-01	21.479
1998-01-01	22.068
1998-04-01	25.160
1998-07-01	26.383
1998-10-01	28.033
1999-01-01	28.583
1999-04-01	30.104
1999-07-01	31.063
1999-10-01	31.285
2000-01-01	32.521
2000-04-01	35.319
2000-07-01	34.272
2000-10-01	35.502
2001-01-01	36.247
2001-04-01	37.132
2001-07-01	38.430
2001-10-01	39.399
2002-01-01	40.430
2002-04-01	44.392
2002-07-01	43.283
2002-10-01	46.059
2003-01-01	49.517
2003-04-01	51.971
2003-07-01	56.531
2003-10-01	61.383
2004-01-01	62.370
2004-04-01	64.790
2004-07-01	65.155
2004-10-01	72.135
2005-01-01	72.812
2005-04-01	72.569
2005-07-01	72.657
2005-10-01	75.845
2006-01-01	79.242
2006-04-01	90.132
2006-07-01	97.029
2006-10-01	106.450
2007-01-01	112.633
2007-04-01	115.026
2007-07-01	124.647
2007-10-01	132.785
2008-01-01	148.346
2008-04-01	163.729
2008-07-01	155.740
2008-10-01	150.859
2009-01-01	150.938
2009-04-01	164.469
2009-07-01	174.120
2009-10-01	175.594
2010-01-01	176.683
2010-04-01	175.348
2010-07-01	194.504
2010-10-01	195.627
2011-01-01	217.118
2011-04-01	226.748
2011-07-01	223.929
2011-10-01	226.973
2012-01-01	243.790
2012-04-01	247.731
2012-07-01	255.707
2012-10-01	261.792
2013-01-01	260.738
2013-04-01	268.677
2013-07-01	276.196
2013-10-01	284.432
2014-01-01	286.433
2014-04-01	280.573
2014-07-01	268.951
2014-10-01	264.573
2015-01-01	256.295
2015-04-01	253.178